Kit -vs- Light
Well, let's examine your options. The restoration kit can be purchased for $15-25 or even more. To use these kits you need a dremel or something similar, they say you can do it by hand and you can, but when I did it I thought my fingers were going to fall off. Plus when you do it by hand it doesn't turn out near as good.
OR
Depending on the type of car you have, you can just get new headlamp housings frm ebay. My wife has an '06 pt and I got her a new after market set for $80.